What is the method to execute tests using a headless browser?

Other Questions Headless Browser
1

I am currently working with Angular CLI, where I execute tests using the command:

ng test

This runs the tests in Chrome by default, which is quite useful. However, I need to know how I can execute these tests in a headless browser for a console-only operating environment. It would also be beneficial to have the option to choose whether to run a browser or not each time I initiate the tests. For instance, something like this:

ng test --browsers MyHeadlessBrowser

Additionally, while trying to use PhantomJS, I encountered this error:

PhantomJS 2.1.1 (Linux 0.0.0) ERROR
TypeError: useValue,useFactory,data is not iterable!

Furthermore, I received this reference error:

ReferenceError: Can't find variable: Intl at vendor.bundle.js (line 49362)

Any guidance on resolving these issues would be greatly appreciated.

2

You can run Angular tests in a headless browser by adding this to your karma.conf.js:

customLaunchers: {
  ChromeHeadless: {
    base: 'Chrome',
    flags: ['--headless', '--no-sandbox', '--disable-gpu', '--remote-debugging-port=9222']
  }
},
browsers: ['ChromeHeadless']

Then, execute tests using:

ng test

Instead of PhantomJS, use ChromeHeadless for better compatibility. Intl issues often relate to older versions or polyfills needed for PhantomJS.

3

To execute tests using a headless browser in an Angular CLI environment, ChromeHeadless is indeed a reliable option due to its compatibility and ease of integration with modern JavaScript features.

Configuration:

To set up ChromeHeadless as your testing environment, you need to modify your karma.conf.js file as follows:

module.exports = function (config) {
  config.set({
    browsers: ['ChromeHeadless'],
    customLaunchers: {
      ChromeHeadless: {
        base: 'Chrome',
        flags: ['--headless', '--disable-gpu', '--no-sandbox', '--remote-debugging-port=9222'],
      }
    },
    // ... other configurations
  });
};

By setting up this configuration, you can use the command:

ng test --browsers=ChromeHeadless

Understanding PhantomJS Issues:

The PhantomJS issue stems from its lack of support for newer JavaScript features, such as Intl. Since PhantomJS is outdated and no longer maintained, it's advisable to switch to ChromeHeadless, which has better support and ongoing development.

Flexible browser selection:

If you wish to keep the flexibility of selecting the browser each time, you can pass the desired browser through the Angular CLI command as shown. However, ensure you have the test environments configured in karma.conf.js for each browser choice.

Moving to ChromeHeadless should resolve the errors and provide a more robust experience for headless test execution in modern web development practices.

4

To execute tests using a headless browser in an Angular CLI setup, I recommend configuring ChromeHeadless instead of using PhantomJS, which can be problematic due to its outdated support for modern JavaScript features.

Setting Up ChromeHeadless:

Update your karma.conf.js with the following configuration:

module.exports = function (config) {
  config.set({
    browsers: ['ChromeHeadless'],
    customLaunchers: {
      ChromeHeadless: {
        base: 'Chrome',
        flags: ['--headless', '--no-sandbox', '--disable-gpu', '--remote-debugging-port=9222'],
      }
    },
    // other configurations
  });
};

Once configured, run your tests with:

ng test --browsers=ChromeHeadless

Why Use ChromeHeadless:

ChromeHeadless is actively maintained and widely compatible with modern JavaScript features, including Intl, which solves the errors you encountered. PhantomJS struggles with such features, resulting in errors like the ones you faced.

Conclusion:

Switching to ChromeHeadless should streamline your testing process and eliminate compatibility issues. You can specify different browsers in the CLI command if you've configured them in karma.conf.js, giving you flexibility without compromising efficiency.

5

To run your Angular tests in a headless browser, you should configure ChromeHeadless in your karma.conf.js rather than using PhantomJS, which is outdated.

module.exports = function (config) {
  config.set({
    browsers: ['ChromeHeadless'],
    customLaunchers: {
      ChromeHeadless: {
        base: 'Chrome',
        flags: ['--headless', '--no-sandbox', '--disable-gpu', '--remote-debugging-port=9222'],
      }
    },
    // other configs
  });
};

After this setup, run your tests with:

ng test --browsers=ChromeHeadless

Use ChromeHeadless for better support of modern JavaScript, avoiding errors like Intl issues you encountered with PhantomJS.